The present invention generally relates to mattresses and, more particularly, to improved air support mattresses and pads for use in the treatment and resuscitation of patents in hospitals, nursing homes and for home care. More specifically, the mattresses, of the present invention provide a cushion of air between the recumbent patient and the supporting mattress or pad, thereby eliminating possible contact therebetween.
Current types of mattresses are relatively non-conformable and cannot limit the pressure at supported body portions supporting to permit the desired free flow of blood and lymph.
It has long been felt desirable to eliminate contact between a patient's body and the suporting mattress, especially in the cases of patients with extensive burns and of patients with incipient decubitus. Living animals of a size comparable to that of humans have been supported for indefinite periods by a broad rising column of air. This method of support has not proved to be practical because the high velocity of the rising column required to support and position the animal tended to damage the healing areas by continual erosion. Further, the level of noise is excessive.
Various systems and devices have been suggested for supporting recumbent patients on a cushion of air. Such systems have incorporated expensive, complicated pressure regulation devices and have required constant adjustment. More recently, as disclosed in Chevrolet U.S. Pat. No. 3,942,202 there has been suggested the use of an elastomeric plate formed with a pressurizable passage connectable with an array of vents. Upon deformation of the plate the vents open into the passage to provide for air flow from the passage through the vents. Accordingly, deflection of the plate caused by the weight of a patient causes air flow from the vents which, according to the Chevrolet disclosure, takes over at least part of the supporting function of the mattress. This prior art device has a disadvantage in that it comprises a relatively thick sheet of rubber material that is quite unyielding to light pressure and unresponsive to small areas of contact.